1. Field of the Invention
The present invention relates to a radiation detection apparatus and a radiation detection system applicable to a medical imaging apparatus, a non-destructive testing apparatus, an analysis apparatus using radiation, or the like.
2. Description of the Related Art
In recent years, thin-film semiconductor production technology has been used in the fabrication of a detection apparatus or a radiation detection apparatus realized by a combination of a switch element such as a TFT (Thin-Film Transistor) and a conversion element such as a photoelectric conversion element. Japanese Patent application Laid-Open No. 07-027864 discloses a radiation detection apparatus in which a solid-state photodetector is disposed on a side on which an X-ray emitted by an X-ray source is incident, and a scintillator is disposed on an opposite side. One of the problems in radiation detection apparatuses, in which the scintillator is disposed on a side opposite to the radiation-incident side, is that the radiation incident on the photodetector undergoes significant scattering. One approach for reducing scattering has been to use a radiation mask or an anti-scatter grid located between the photodetector and the X-ray source. However, the use of an external mask or grid attenuates the level of radiation incident on the photodetector. Another solution for reducing scattering of radiation has been to fabricate a photodetector with a built-in anti-scattering grid. However, it is difficult to determine the position of the grid. Moreover, Japanese Patent application Laid-Open No. 07-027864 does not disclose a location at which a grid for enhancing image sharpness is disposed, although the location of the grid is to be properly determined to handle scattered radiation.